Improvement in apparatus for mixing air and gas



THOMAS c. HOPPER.

Improvement in Apparatus for Mixing Air and Gas.

N0. 121,719. Patented Dec.12,187I.

FIG. I1

PATENT QFFICE.

THOMAS C. HOPPER, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN APPARATUS FOR MIXING AIR AND GAS.

Specification forming part of Letters Patent No. 121,719, dated December 12, 1871.

To all whom it may concern:

Be it known that I, THOMAS (J. HOPPER, of the city of Philadelphia, in the State of Pennsylvania, have invented certain improvements in the apparatus for mixing different gases or rich carbo-hydrogens with atmospheric air in any required proportions, of which the following is a specification:

The mixers heretofore used consist of two ordinary gas-meter drums fixed on one shaft so as to rotate together within a case containing water at about two-thirds of the depth of the drums, each drum being divided into four compartments by spirally-arranged partitions, each of which has an offset, a b, at its mid-length. The gas coming from the retorts is the motive power, and enters the gas-drum through a pipe which is bent so as to pass the gas up through the water and discharge it above the water-line in the drum. The pressure in the retorts and main upon the gas causes the latter to press successively upon the offsets a b of the partitions above named, and thus cause the drum to rotate in the water and allow the gas to pass between the partitions into the case containing both drums and the airdrum, being fixed on the shaft of the gas-drum, as before stated, is necessarily rotated simultaneously with the latter, taking in atmospheric air and discharging it into the case common to both drums, from which the gas and air pass out mixed. Some mixers have the gas-drum and the air-drum in separate cases, and the two drums connected by outside gearing adapted to give them the respective rotary motions required to pass the desired proportions of gas and air; but in either case the two drums are driven by the pressure of the gas upon the offsets a b of the partitions (before described) of the gas-drum only, and as the said offsets of the partitions have to be moved through the water by the pressure of the gas in the retorts and main the rotary motion of the drums will be very slow; and consequently very large and costly drums and cases are required to be used, especially when the amount of gas to be consumed in a short time is large; and hence various devices, such, as springs, weights, water-wheels, 850., have been resorted to for the purpose of increasing the speed. The principal object of my invention is to increase the actual working capacity of the mixing-drums, in order that a much smaller, and therefore less costly,

pair will be fully adequate to the purpose, and the retorts and main be entirely relieved from the pressure heretofore required to propel the gas forward and drive the drums. These purposes I accomplish by constructing the spirally-arranged partitions (which divide the drums into passageways for the gas and the air, respectively) without the offsets before mentioned, and thus allow the partitions to slip through the water in the cases with the least resistance possible; and by giving rotary motion to the drums by means of steam or other motive power applied to pulleys fixed on the shaft or shafts of the drums outside of the water-case or cases in which the said drums are rotated, and thus not only relieve the gas-retorts from the pressure heretofore required to drive the drums, but actually drawing the gas out of the retorts and main by an exhaustive action of the gas-drum.

Figure 1 is a plan or top view of the gas-drum and the air-drum in their respective water-cases,

connected together by the exit-pipes, the tops of the cases being removed in order to expose the arrangement of the drums in their cases. Fig. 2 is a vertical central longitudinal section of the gas-drum audits water-case embodying my invention. Fig. 3 is a plan view of one of the spirally-arranged partitions of the drums detached. Fig. 4 is an end view of the gas-drum and its case, with the case bisected transversely in order to show the open end of the drum. Both the gas-drum and the air-drum are constructed alike. Fig. 5 is a modification of the spiral passageways and partitions of the drums.

The gas-drum A and the airdrum B are hollow cylinders provided with six sections (more or less) of plain or even-surfaced spirally-arranged partitions to I), having their outer edges soldered or otherwise secured gas'tight in the usual well-known manner to the interior of the perimeters of the cylinders, so as to produce corresponding spiral passage-ways between them for the gas or air to be taken in at one end and discharged at the other of the said ways as the said cylindrical drums are being rotated on their respective shaftbearings in the water, the surface line of which latter reaches to a sufficient height above the usual central openings in the hoods a b of the drums A and B to effectually keep sealed the said openings. Each of the partitions a b is cut out of a flat plate of sheet metal, substantially and even or without any ott'set whatever on its 1 surtace. shown in Figs. 2 and 4, and it will be seen that each spiral channel between the partitions(which overlap each other at their ends) will successively be closed at the end which enters the water before its Opposite end rises out of the same, the dotted line .I being the surface Iincot' the water; and that, as the sides of each of the partitions are plain or without any offsets, they will all move or slip through the water with the least obstruction possible, and, theretore, without pro duciug any objectionable agitation of the water even at a rapid speed. The drums A and Bare each driven by any suitable motive power applied outside of the cases to a stepped band-pulley, 3, on that end of the shaft of each which projects through the central openings in the rear of the cases into an open box, 4, in which the same water-line is maintained through the openings, and the latter scaled thereby. The gasmaiu lrom the retorts is intended to be attached to the orifice at the top of the case containing the gas-drum A; but a like orifice at the top of the case containing the air-drum I3 is intended to be left open for the free entrance of the air. The bent pipes ti and T, which pass up and open above the water-line .1" of the cases. communicate at their opposite ends with a main pipe, which is intended to lead into the usual gasometer. and. consequently, when rotary motions are simulta neously given to the gas drum A and the airdrum B the two fluids will be conveyed through the bent tubes or pipes (i and 7 into the main s, whence they will be discharged into the intend ed gasometer mixed in proportions governed by the relative speed given to the two drums A and B. It will also be seen that the operation ot'the gas-drum A is exhaustive in relation to the retOrts, and hence the pressure heretolore required Of the latter to drive the drums is wholly or entirely avoided, and consequently the large and costly mixers heretotorc required to be made with Oii'sets in their partitions can be superseded by the comparatively small and inexpensive mixers herein set forth, because the partitions of the latter, being free from oti'sets, will slip through the Water with the least possible resistance there- 'lhc arrangement of the partitions is t rom and the drums be driven with proportionately increased speed. Moreover, the cubical contents pel' rotation of each drum being ascertained, and an index placed in connection with each shaft, the working results of either or of both combined will be accurately shown, and the apparatus be a combined exhauster, mixer, and meter. The modification shown by Fig. 5, in which partitions a" a" in the. form of scrolls are secured between two flat disks, with the usual hood at one end, will move or slip through the water with the same freeuess and rapidity as those just previously described; and it is intended to make use of this form, Fig. 5, in instances where it may be preferred.

1 am aware that two gas-meter drums have been connected together by one shaft so that the pressure of gas used as the motive power of one will drive. the other also, as in the American patent of larrish, No. 38,499; and also that mechanical devices, as weights, water-wheels, and gearing, have been applied outside of gas-meters to aid in driving the old-fashioned drums, the hoods or partitions of which have each the obstructive ot't'set before described, which in some instances renders it necessary to add such out.- side motive power, as in the English patent of Lowe, No. 8,883. Therefore I do not desire to claim, broadly, theapplicationot' outside mechanical power to drive a gas-meter drum;' but What I desire to secure by Letters Patent is contined to the tbllowing:

l. The plain continuous flat-surfaced partitions 1!, in combination with the cylinders of the drums A and B of a mixer, substantially as and tor the purposes hereinbetbre set forth.

2. In a mixer the drums of which are provided with the plain continuous flat-surfaced partitions u, as described, the arrangement and mode of operation whereby the gas-drum A and the airdrum 13 are driven by a motive powe' applied outside ol' their respective water-cases and the gas-drum caused to act exhaustively in relation to the retorts and supply main, substantially as and for the purposes hereinbet'ore set forth.

THOMAS C. HOPPER.

\Yitnesses:

BnxJ. MoiusoN,

HENRY CARTWRIGHT. (6U) 

